linux-kernel - Re: drm: WARNING in ioremap

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [day] [month] [year] [list]

Date:   Fri, 2 Sep 2016 14:40:49 +0200
From:   David Herrmann <dh.herrmann@...il.com>
To:     Dmitry Vyukov <dvyukov@...gle.com>
Cc:     David Airlie <airlied@...ux.ie>,
        "dri-devel@...ts.freedesktop.org" <dri-devel@...ts.freedesktop.org>,
        LKML <linux-kernel@...r.kernel.org>,
        Thomas Gleixner <tglx@...utronix.de>,
        Ingo Molnar <mingo@...hat.com>,
        Kostya Serebryany <kcc@...gle.com>,
        syzkaller <syzkaller@...glegroups.com>,
        Alexander Potapenko <glider@...gle.com>
Subject: Re: drm: WARNING in ioremap_wc

Hey

On Fri, Sep 2, 2016 at 2:23 PM, Dmitry Vyukov <dvyukov@...gle.com> wrote:
> On Mon, Aug 29, 2016 at 8:05 AM, Daniel Vetter <daniel@...ll.ch> wrote:
>> On Sun, Aug 28, 2016 at 07:36:59PM +0200, Dmitry Vyukov wrote:
>>> Hello,
>>>
>>> The following program triggers WARNING in ioremap_wc:
>>
>> Yup, that should also be fixed in linux-next. Probably better to not
>> report more for 4.8-rc kernels for now ;-)
>>
>> If you have some time to test, you need to cherry pick the following two
>> patches I think:
>>
>> fa5386459f06 ("drm: Used DRM_LEGACY for all legacy functions")
>> 3cbf6a5deb2f ("drm: Mark up legacy/dri1 drivers with DRM_LEGACY")
>>
>> If that's confirmed we can cherry-pick them over to -fixes.
>
>
> Hi Daniel,
>
> I've switched to linux-next and don't see the WARNINGs anymore.
> I wonder how they were discovered? Is somebody else running syzkaller?
> Or they were discovered in some other way?

We independently discovered that some DRM-KMS drivers enabled the DRI1
ioctls, and fixed this. Hence, you should be unable to trigger
anything in drm_bufs.c, drm_context.c, and friends.

Thanks
David